<template>
  <div :class="className" :style="{ height: height, width: width }">
    <!-- 图表容器 -->
    <div ref="chartContainer" style="width: 100%; height: 100%;" />
  </div>
</template>

<script>
import echarts from 'echarts'
require('echarts/theme/macarons') // echarts theme

// 处理月份数据
function padMonthData(expectedData, monthLabels) {
  if (expectedData.length >= 12) {
    return {
      expectedData: expectedData.slice(0, 12),
      monthLabels: monthLabels ? monthLabels.slice(0, 12) : ['一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月']
    }
  }

  const defaultMonthLabels = ['一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月']
  
  const paddedData = [...expectedData, ...Array(12 - expectedData.length).fill(null)]
  const paddedLabels = monthLabels 
    ? [...monthLabels, ...defaultMonthLabels.slice(monthLabels.length)]
    : defaultMonthLabels

  return {
    expectedData: paddedData,
    monthLabels: paddedLabels
  }
}

export default {
  props: {
    className: {
      type: String,
      default: 'chart'
    },
    width: {
      type: String,
      default: '100%'
    },
    height: {
      type: String,
      default: '350px'
    },
    chartData: {
      type: Object,
      required: true
    }
  },
  data() {
    return {
      chart: null
    }
  },
  watch: {
    chartData: {
      deep: true,
      handler(val) {
        this.setOptions(val)
      }
    }
  },
  mounted() {
    this.$nextTick(() => {
      this.initChart()
    })
  },
  beforeDestroy() {
    if (this.chart) {
      this.chart.dispose()
    }
  },
  methods: {
    initChart() {
      this.chart = echarts.init(this.$refs.chartContainer, 'macarons')
      this.setOptions(this.chartData)
    },
    setOptions({ expectedData, monthLabels } = {}) {
      const { expectedData: paddedData, monthLabels: paddedLabels } = padMonthData(expectedData, monthLabels)
      this.chart.setOption({
        xAxis: {
          data: paddedLabels || ['一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月'],
          boundaryGap: false,
          axisTick: {
            show: false
          },
          axisLabel: {
            rotate: 45 // 旋转45度
          }
        },
        grid: {
          left: 10,
          right: 20,
          bottom: 20,
          top: 30,
          containLabel: true
        },
        tooltip: {
          trigger: 'axis',
          axisPointer: {
            type: 'cross'
          },
          padding: [5, 10]
        },
        yAxis: {
          axisTick: {
            show: false
          },
          axisLabel: {
            show: true
          }
        },
        legend: {
          data: ['pH值']
        },
        series: [{
          name: 'pH值',
          itemStyle: {
            normal: {
              color: '#3888fa',
              lineStyle: {
                color: '#3888fa',
                width: 2
              }
            }
          },
          smooth: true,
          type: 'line',
          data: paddedData,
          animationDuration: 2800,
          animationEasing: 'cubicInOut'
        }]
      })
    }
  }
}
</script>